So, another busy week on site – we have moved on now into the realms of “proper” building – construction of the new fabric. Having insulated the external walls with celotex, we are now floating in the suspended ceiling to the ground floor and also lifting the boarding of the living space above to prepare for the installation of the underfloor heating – between the joists to save headroom.
This process has thrown up a couple of things – firstly how little insulation the original construction had – considering the conversion from flats to ‘town house’ was only done in the mid 90s, it seems crazy that there was literally nothing between the floors for acoustic separation – apart from 50mm mineral wool thermal/fire insulation above the old garage space. We have decided to retain this to save on waste – after all the more acoustic insulation between the garage (to become a studio where our client can play the drums) and the living space the better. Waste not want not.
So – we are also floating in a new ceiling downstairs using a suspended metal firring system, great that the ceilings were high enough to do it in this mews property – maybe once accommodated a horse & carriage? This has several benefits –

structure for new floating ceiling on the ground-floor (we will insulate above this ceiling with Earthwool to reduce acoustic transmittance between floors)
1. above this ‘false’ ceiling we will install 100mm of Earthwool Acoustic Roll (made from recycled glass bottles) and so reduce the sound passing between floors – a particular request from the clients to prevent the bedrooms on the ground floor being affected by people activity upstairs. The firring system lessens the impact sound through the structure as well as airborne noise.
2. this space also allows us to hide all the new services: electrics & recessed lights, ventilation routes for our planned MVHR system, and the new plumbing supplies from the new boiler heatstore & solar from upstairs to the bathrooms and underfloor heating system.

on instructions from the second Structural Engineer we have secured the rafters to the cross ties in the living space
As if this wasn’t enough to get done this week – we have also completed the upgrades to the structure of the roof as directed by the Structural Engineer. (We got a second opinion on the solution for this, the first proposed much drilling and bolting into the heavy steels which for our gearing was inappropriate). A lesson learned there – a problem can have other solutions, it depends who you ask and how you put the question.
Finally, we have also begun the process of installing our airtightness membrane. We are using ‘Intello Plus’ which was recommended to Alex by one of his AECB contacts as the best on the market – look up http://www.ecomerchant.co.uk/content/pro-clima-intello-plus
All in all another busy week. Now more insulation in the floor upstairs to sit immediately below the underfloor heating, the MVHR vent system to install, and the new structure in the dining room to form next week – that should keep us busy!!
Our clients are desperate to get out of their temporary ‘holiday let’ which has proved less than comfy, so it begins to feel like those telly formats where the excitement is always wound up by the too-tight fast-approaching deadline. We’ll avoid shortcuts though, in real life it’s not worth it – watch this space, things may get hairy.